System for monitoring animals in motion

ABSTRACT

A system for monitoring animals such as horses in motion, such as during swimming exercise, wherein suction cup attached electrodes on the animal are connected by leads to one or more heart action-measuring instruments such as an electrocardiograph and a pulse rate meter, the suction cup, electrodes and all junctures being of similar metal to prevent electrolytic interference with the electrocardiograph-actuating impulses. The suction cups are connected to a powered vacuum source.

United States Patent [72] Inventors Max B. Kirkpatrick:

Andrew G. Harvey; John .Sparks, 111, all of Box 1509, Wickenburg, Ariz.85358 [21] Appl. No. 19,519 [22] Filed Mar. 17,1970 I Division of Ser.No. 638,719. Nov. 16. 1967 which is a continuation of Ser. No. 781,038,

Dec. 4, 1968, abandoned [451' Patented July 27, 1971 [54] SYSTEM FORMONITORING ANIMALS IN MOTION 6 Claims, 5 Drawing Figs. I

l28 lDlGi 4 [51] 1nt.Cl A61 b 5/04 [50] Field ofSearch 128/205,

Primary Examiner-William E. Kamm Attorney-Strauch, Nolan, Neale, Niesand Kurz ABSTRACT: A system for monitoring animals such as horses inmotion, such as during swimming exercise, wherein suction cup attachedelectrodes on the animal are connected by leads to one or'more heartaction-measuring instruments such as an electrocardiograph and a pulserate meter, the suction cup, electrodes and all junctures being ofsimilar metal to prevent electrolytic interference with theelectrocardiograph-actuating impulses. The suction cups are connected toa powered vacuum source.

PATENTEO JUL27 :91:

INVENTORS MAX a KIRKPATRICK ANDREW a. HARVEY 7 BY JOHN M. SPAR/(5,122afimw, $50M. Wm

ATTORNEYS SYSTEM FOR MONITORING ANIMALS IN MOTION This is a continuationof our earlier application Ser. No. 78 l ,038 filed Dec. 4, 1968 forSystem for Monitoring Animals in Motion, and now abandoned, said earlierapplication having been a division of our copending application Ser. No.683,719, filed Nov. 16, 1967 for Monitored and Controlled Conditioningand Exercise Method for Animals.

BACKGROUND AND SUMMARY OF INVENTION The invention relates to anelectrical system whereby the instantaneous condition of animals inmotion may be continually monitored. For example, it will be disclosedas applied to a system for operatively connecting an electrocardiographand a heart rate meter to a swimming horse. Special suction cupelectrodes are employed.

While electrocardiograms are well known, they are universally taken withthe patient or animal in a state of complete inaction, becauseexperience has shown that motion normally induces undesired electricalsignals from other than heart muscles.'Also suction cups per se forattaching electrocardiograph leads are known. To applicants knowledgehowever, it has never been possible to take an electrocardiograph of ananimal in violent motion, and this is a major object of the presentinvention.

It is another object of the invention to provide a novelelectrocardiograph and like instrument lead system wherein metal suctioncups to be attached to an animal in exercise such as swimming areconnected to the instrument by leads of similar metal to reduceelectrolytic side effects. I

A related object of the invention is to include a powerful source ofvacuum in the system for holding the electrodes immovable on the animal.

A further object of the invention is to provide a novel suction cup-typeelectrode, Further and more detailed objects will appear in thespecification and claims.

The invention is useful in the selection and controlled conditioning ofanimals, particularly race horses although its basic aspects may beapplied to humans.

Prior to the invention it has always been common practice to conditionand train horses for racing using traditional methods which vary widelybetween individual trainers but in all of which the horses are exercisedby actual running and their condition ascertained only by visualobservation and/or by feeling chest and leg muscles. Experience hasshown that horses undergoing such training are likely to accidentallyphysically injure their legs in one way or another during running,usually because of early fatigue due to poor or inadequate conditioning.Furthermore, there is no way to accurately discover during such trainingwhether the horse is being exercised excessively or in such manner as tocause internal damage.

As a result of these haphazard training methods, many capable horsessuffer premature injury and never reach the track, and many of those whodo reach the track are so overtrained as not to be in optimum conditionat the time.

The invention enables for the first time an optimum substantiallyinjury-free conditioning exercise program wherein the animals heartaction is continually monitored to prevent excesses, and such is a veryimportant object.

The invention enables controlled cyclic conditioning exercise of theanimal monitored to prevent overtraining, this comprising vigorouslyexercising the animal during periods of high heart beat near but undersafe values determined by test on the particular animal, such periodsbeing spaced by nonexercising recovery intervals during which the heartbeat is allowed to drop to a safe value for resuming the exercise, allthe while continually monitoring the animal's heart action to determinethe length of these periods and intervals.

The invention will be explained in detail with regard to race horsetraining which is its preferred application.

An important step is the proper selection of a colt. It is preferable toselect colts at the age of 6 months. It is known that a horse's heartsize changes between birth and the age of IS months more than at anyother time. For this reason, it is important that concentrated exerciseoccurs from weaning (6 months) to age two. However the invention may beapplied to horses of any racing age. For purposes of simplicity the termhorse includes colts.

Two major factors in selection are conformation and size of the heart asdetermined by observation of an electrocardiogram and measurement of thewidth of the QRS complex. The QRS width is the time an electricalimpulse takes to travel through the muscle mass of the ventricles andthis width is directly proportional to the muscle mass of the heartventricles and therefore it is a measure of heart size. This QRS widthwould be final determination as to whether or not the colt is selectedor rejected, because normally only horses with defect-free large heartsize may become efficient winning race horses.

An electrocardiogram for a particular horse is studied, not only foracquainting the veterinarian with the size of the heart, but also forexamination of the T-wave position and amplitude. When a horse iscompletely out of condition for racing, the T-wave ontheelectrocardiogram is positive in location and high in amplitude, on aunipolar base apical lead, at

rest. As the horse becomes conditioned the T-wave becomes negative inpolarity and greater in amplitude in the negative direction. This is animportant determination as to whether or not the horse is fit from anelectrocardiogram standpoint.

The horse begins active conditioning with the swimming exercise cycleprogram. The horse is preferably exercised in the following manner. Heis placed on an elevator platform above a body of water and restrainedfrom appreciable movement front, rear andlaterally, care being taken notto physically restrain in any way the legs or any muscles used inswimming. A heart condition meter in the form of an electrocardiographand a heart rate meter are connected to his body by means of specialsuction devices as will appear. His heart action is continuallymonitored during the entire program. He is lowered into the water untilhe is forced to swim and so remains until his heart is observed toattain a steady rate of approximately 200-225 beats per minute dependingon the horses normal. Instantly, at that point, the horse is raised outof the water far enough so that he may breathe as freely as possible andstop swimming. This is preferably done by raising the platform until hecan stand on it. He is raised to such height that the lung cavity iscompletely out of the water so that there is no hydrostatic pressureagainst the lungs when he is in a state of oxygen debit induced by theexertion. The recovery interval now starts. The heart rate meter andelectrocardiogram are watched until his reducing heart rate reaches apoint on the electrocardiograph where the T-P base line becomesdiscernible and the T-wave shape indicates the start of reversal. Theheart rate at this point may be within the neighborhood of I40 beats perminute depending on the individual. Either meter may be used todetermine this period. When the individuals,heart rate reaches the lowrange the recovery interval is over and he immediately is returned tothe water by lowering the platform so that he is again forced to swimuntil his heart rate arrives at approximately 200-225 again. Inpractice, the length of this recovery interval is carefully noted, asrecovery rate is a barometer of the horse's condition. The wholesequence is repeated cyclically to the end of the exercise.

With this particular manner of conditioning horses, a horse may alwaysbe maintained in condition from the time he is 6 months of age until heis through with his racing career, for all practical purposes. It doesnot damage the horse to be kept in constant condition as long as itneeds to be kept in condition and can run. It is actually easier for ahorse to be kept in condition rather than to let it down at the end ofeach racing schedule but the main advantage is heavy exercise can bemaintained without damage to the horses legs.

One of the major advantages in swimming a horse for exercise is that ahigh heart rate can be obtained and safely maintained, and by theinvention the horse can be continually monitored so as to obtainrecovery rates at rest intervals and the use of this as a barometer ofthe animals change in condition. Heart action monitoring as is obtainedin the invention is moreover not possible in a running horse. The betterthe condition the more rapidly the animal returns to normal. A horsethat is trained at a high heart rate level at periodic intervals willdevelop more capillaries in the muscular tissue and more venouscapillaries for the return of carbon dioxide and lactic acid duringexercise, thereby making a more efficient machine which will operate atgreater capabilities, more efficiently, for longer periods.

BRIEF DESCRIPTION OF DRAWINGS FIG. I is a diagrammatic view showing themonitored interval swimming exercise program wherein the invention isused;

FIG. 2 is a diagrammatic view showing preferred placement of themeasuring instrument leads on a horse undergoing the interval swimmingexercise program of FIG. 1;

FIG. 3 is a specimen section of an electrocardiograph taken on a horseat rest;

FIG. 4 is a specimen section of an electrocardiograph taken during anactual exercise period of a vigorously swimming horse; and

FIG. 5 shows a preferred suction cup structure used for attachingelectrocardiograph and heart rate meter leads to the horse during theexercise program.

PREFERRED EMBODIMENTS The invention is used for the controlled exerciseof a selected animal.

Applicants have found that the optimum manner ofcontrollably exercisingan animal such as a horse for racing is swimming. This is mainly becauseswimming utilizes essentially all of the major muscles used in running,and swimming takes place in an environment wherein the horse is leastsubect to injury.

Swimming moreover is an exercise which causes a relatively greatincrease in cardiac output to supply needed oxygen to the muscles.Several factors other than the exercise itself, namely, increased heatloss, respiratory stimulation, and-pressure of the water, areresponsible for the greater cardiac response in this type of exercise. Alarge heart will be capable of handling most increased venous returncaused by vigorous exercise without appreciable increase in heart rate,and therefore by increasing the rate of beat of such a heart duringviolent exercise such as strong swimming it maintains a constant highoutput adequate to handle the corresponding increased venous return, andso increase the total circulation with more blood being delivered to thecapillaries to supply oxygen to the muscles for sustained effort.

In conditioning a horse as shown in FIG. I, the animal is placed on aplatform 11 elevated above a confined body of water indicated at 12 andrestrained from lateral, forward and rearward movements of the platform.This restraint is applied to the upper part of the body as by strapswell above the legs, or by connecting the tail to a stable bar behindthe horse, so that there is no mechanical interference with normal legmovement or shoulder and upper rear leg muscles or respiratory actionduring swimming.

FIG. 1 diagrammatically illustrates the cycle of swimming exercise underthe invention. Position 0 in FIG. 1 indicates the start of the exerciseperiod. This position may be above water level to enter the horsedirectly onto the platform.

The platform, with the animal thereon, is lowered gradually into or inthe water until at the position indicated at 11' submersion is such thatthe animal must swim to remain afloat. Swimming tends to propel theanimal forwardly, but this movement is prevented by the front restraintso that effectively the animal remains longitudinally substantially inthe same place while the legs move through the water.

While the animal is swimming its heart is closely monitored. The effortof swimming will cause the heart rate to rise, in proportion to theenergy being exerted, and a sustained high heart rate above a certainsafe value, which value will be indicated for that animal by theforegoing physiological analyses and electrocardiograms, will result inharmful fatigue rather than beneficial conditioning.

The heart action is constantly measured during the exercise cycle by aspecial combination of novel body attached electrodes shown at 13 and 14and an electrical instrument 15 capable of detecting and measurablyindicating the very small generated voltages incident to heart action,in the neighborhood of l to 3 millivolts, such as an electrocardiographwhich may be also serve as a heart rate meter. Alternatively a separateheart rate meter may be connected to the leads as part of instrument 15.As will be described, the electrodes are special suction cups attachedas by lines I6, 17 to an external source of vacuum 18.

It is absolutely essential that there be no extraneous electricalsignals to vary or mask the potentials generated by heart muscle actionwhich operate the electrocardiograph. Therefore the electrodes 13 and 14are preferably attached to the horse's body at the illustrated points inFIG. 2 where adjacent muscular activity is minimum notably near the topof the front shoulder and at the underside of the body near the frontleg. It is further essential that the electrodes make good unvaryingcontact with the horses body, and that is the function of the externalvacuum which in exercises to date indicate that a vacuum of about 25inches of mercury is satisfactory to anchor the electrodes to the bodyso as to prevent any static generating movement thereof relative to thebody even when the horse is swimming vigorously.

As shown in FIG. 5 each vacuum line 16 (or 17) is a vinyl or likenonconducting plastic tube 21 fitted upon a stainless steel collar 22welded airtight into an aperture in a shallow noncollapsible stainlesssteel cup 23. The end of a stainless steel wire 24 is welded at 25 tocollar 22, and the wires 24 emerge from the tubes 21 in an insulatingsheath 20 for connection to meter assembly 15, so that the wires 24 areelectrically insulated from each other between their respectiveelectrodes and the meter assembly. Preferably the tubes 21 of lines 16and 17 are joined to a single tube 26 leading to vacuum source 18, sothat the vacuum is connected to simultaneously act on the electrodes.

The importance of the external suction lies in its ability to exertsufficient force to properly anchor electrodes 13 and 14. Suction bulbshave been proposed for electrodes in human electrocardiography, but suchwould not be adequate for attachment to vigorously exercising horses. Weknow of no instance where electrocardiographs have been taken ofvigorously exercising humans during exercise, so that the problemssolved by this phase of the invention have never been presented orrecognized.

In actual practice it was discovered that the presence of chlorine andlike substances in the water containing the swimming horse resulted insufficient electrolytic action at electrodes containing junctures ofdissimilar metals to produce misleading signals in the meter leads.Hence care is taken in the invention to eliminate this difficulty, and acurrent solution is to use the same metal along the entire conductivepath between the horse's body and the meter 15. In practice the suctioncups 23 and collars 22 are formed of 316 stainless steel about 0.035inch thick, and wires 24 are 316 stainless steel. Welding is done with a316 stainless steel welding rod. Therefore the conductive metalcomposition is uniform along its entire length, and no electrolyticeffects are present.

Referring to FIG. 5, it will be noted that application of vacuum to tube21 results in the skin 27 of the horse being pulled into closedconformity with the interior of the cup 23, with the sharp annular edge26 of the cup indenting (but not cutting) the skin. This provides a goodlocking attachment which does not change position or become detachedwhen the horse is swimming. We believe that such strong attachment ofthe electrodes and selection of regions of the horse's body whichundergo little movement when the horse is exercising mutually contributeto the clarity with which the heart action signals are received on theelectrocardiograph and the heart rate meter during exercise.

A weight-indicating system 28 including a scale dial 29 measures thehorse s weight when the platform is free of the water, as shown in FIG.I.

The measuring system including attachment of electrodes 13 and 14 isplaced usually when the horse enters to position a in FIG. 1 and is innormal equilibrium. Then his heart action is measured, and he is loweredto swimming position b during which the electrodes remain attached.

In position b, monitoring of the heart action continues. As soon as themeasured heart rate reaches the upper limit range (200-225 beats/minute)the platform is raised toward position 11 until the horse can findfooting, is no longer swimming, is standing on the platform as shown ata in FIG. 1 and is breathing easier as above explained. Now the recoveryinterval starts and during this interval constant monitoring of theheart action continues and the horse's rate of recovery is noted.

When the lowering heart rate reaches a predetermined range, usuallybelow I40 beats/minute, or when the P-T line becomes discernible on anelectrocardiogram, the platform is again lowered as at b in FIG. 1 untilthe animal is forced to resume his swimming. The duration of therecovery interval is noted.

The foregoing is repeated several times, the animal being thus violentlyexercised by swimming for successive periods at high heart beat levelsand allowed to partially recover between periods of exercise. Inversionof the T-wave from negative in FIG. 3 to positive in FIG. 4 indicatesthat the animal is in condition. I

During conditioning, the horse is given this swimming exercise cycle onthe average of about once a day and he is weighed each day about thesame time. As training progresses and the horse becomes conditioned itwill be noted that the exercise period in cycle time gradually increasesand the recovery interval decreases which is an indication thatendurance is increasing. Each exercise period lasts a reasonable time,usually about 3- minutes depending on the horse and his currentcondition. The conditioning period may last up to about 3 to 6 weeks,but this may vary for individuals.

The foregoing described conditioning is safe and humane, and itunexpectedly improves a horses endurance capabilities. Constantmonitoring of the heart action insures that the horse never reaches thefatigue point between recovery intervals. Continual monitoring ofrecovery is equally important. The quicker the horse's heart rate dropsfrom 200225 to I00- I40 beats per minute during a recovery intervalbetween swimming periods the better the horse's condition. The quickerthe horse's heart rate recovers to the equilibrium normal following theexercise ofa conditioning cycle, whether the exercise be swimming orrunning, the better the horse's condition.

The embodiments ofthe invention in which we claim an exclusive propertyor privilege are defined as follows:

1. A measuring system for continually monitoring an animal takingviolent exercise comprising a plurality of rigid noncollapsible metalsuction cup electrodes for direct attachment to spaced selected areas ofthe animals skin for determining potentials arising from heart action,means providing an apertured hollow fitting on each electrode, aflexible tube of electrically insulating material connected between eachfitting and adapted to be connected to an external source of vacuum, anda flexible metal electrical conductor attached at one end within each ofsaid electrodes and extending away from the electrode within theassociated one of said tubes, whereby each electrode is operable in ahostile, aqueous environment, a heart action meter, and electricallyinsulated means remote from the electrodes conveying the other ends ofall of said conductors from said tubes into operatlve connection withsaid heart action meter, and means defining a downwardly projectingsharp annular edge about the lower periphery of each suction cup wherebyeach suction cup is firmly engaged with the skin of the animal withoutcutting the skin.

2. In the system defined in claim I, said conductors suction cup andfittings all being composed ofthe same metal.

3. In the system defined in claim 2, said metal being stainless steel.

4. In the system defined in claim 1, said meter being anelectrocardiograph.

5. In the system defined in claim 4, said meter including a heart ratemeter.

6. In the system defined in claim 1, each suction cup having asubstantially uninterrupted interior skin contact portion for maximumsurface contact of each suction cup with the skin of the animal beingmonitored.

1. A measuring system for continually monitoring an animal takingviolent exercise comprising a plurality of rigid noncollapsible metalsuction cup electrodes for direct attachment to spaced selected areas ofthe animal''s skin for determining potentials arising from heart action,means providing an apertured hollow fitting on each electrode, aflexible tube of electrically insulating material connected between eachfitting and adapted to be connected to an external source of vacuum, anda flexible metal electrical conductor attached at one end within each ofsaid electrodes and extending away from the electrode within theassociated one of said tubes, whereby each electrode is operable in ahostile, aqueous environment, a heart action meter, and electricallyinsulated means remote from the electrodes conveying the other ends ofall of said conductors from said tubes into operative connection withsaid heart action meter, and means defining a downwardly projectingsharp annular edge about the lower periphery of each suction cup wherebyeach suction cup is firmly engaged with the skin of the animal withoutcutting the skin.
 2. In the system defined in claim 1, said conductorssuction cup and fittings all being composed of the same metal.
 3. In thesystem defined in claim 2, said metal being stainless steel.
 4. In thesystem defined in claim 1, said meter being an electrocardiograph.
 5. Inthe system defined in claim 4, said meter including a heart rate meter.6. In the system defined in claim 1, each suction cup having asubstantially uninterrupted interior skin contact portion for maximumsurface contact of each suction cup with the skin of the animal beingmonitored.